Cathode of mercury cell is made up of

Solution:

A mercury cell is a type of primary battery. In a mercury cell, the anode is a zinc-mercury amalgam, and the cathode is a paste of mercury(II) oxide (HgO) and carbon. The electrolyte used is a paste of KOH and ZnO.

At the cathode, the reduction reaction is:

HgO(s) + H₂O(l) + 2e⁻ → Hg(l) + 2OH⁻(aq)

Therefore, the cathode is made up of a paste of HgO and carbon.